The Experts below are selected from a list of 7287 Experts worldwide ranked by ideXlab platform
Koichi Ohno - One of the best experts on this subject based on the ideXlab platform.
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adsorptive virus removal with super Powdered Activated Carbon
Separation and Purification Technology, 2013Co-Authors: Taku Matsushita, Hideaki Suzuki, Nobutaka Shirasaki, Yoshihiko Matsui, Koichi OhnoAbstract:Abstract We investigated the removal of bacteriophages by adsorption on commercially available Powdered Activated Carbon (N-PAC, median diameter >10 μm) and super-Powdered Activated Carbon (S-PAC, median diameter 0.7–2.8 μm). N-PACs failed to remove the virus in Milli-Q water buffered with 100 μM Ca 2+ , but some S-PACs successfully removed it under the same condition. Three factors contributed substantially to virus removal: a smaller electrophoretic repulsive force between the virus and the PAC particles, a large proportion of pores 20–50 nm in diameter, and a greater hydrophobicity of the virus surface.
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modeling high adsorption capacity and kinetics of organic macromolecules on super Powdered Activated Carbon
Water Research, 2011Co-Authors: Yoshihiko Matsui, Taku Matsushita, Naoya Ando, Tomoaki Yoshida, Ryuji Kurotobi, Koichi OhnoAbstract:The capacity to adsorb natural organic matter (NOM) and polystyrene sulfonates (PSSs) on small particle-size Activated Carbon (super-Powdered Activated Carbon, SPAC) is higher than that on larger particle-size Activated Carbon (Powdered-Activated Carbon, PAC). Increased adsorption capacity is likely attributable to the larger external surface area because the NOM and PSS molecules do not completely penetrate the adsorbent particle; they preferentially adsorb near the outer surface of the particle. In this study, we propose a new isotherm equation, the Shell Adsorption Model (SAM), to explain the higher adsorption capacity on smaller adsorbent particles and to describe quantitatively adsorption isotherms of Activated Carbons of different particle sizes: PAC and SPAC. The SAM was verified with the experimental data of PSS adsorption kinetics as well as equilibrium. SAM successfully characterized PSS adsorption isotherm data for SPACs and PAC simultaneously with the same model parameters. When SAM was incorporated into an adsorption kinetic model, kinetic decay curves for PSSs adsorbing onto Activated Carbons of different particle sizes could be simultaneously described with a single kinetics parameter value. On the other hand, when SAM was not incorporated into such an adsorption kinetic model and instead isotherms were described by the Freundlich model, the kinetic decay curves were not well described. The success of the SAM further supports the adsorption mechanism of PSSs preferentially adsorbing near the outer surface of Activated Carbon particles.
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Geosmin and 2-methylisoborneol adsorption on super-Powdered Activated Carbon in the presence of natural organic matter.
Water Science and Technology, 2010Co-Authors: Yoshihiko Matsui, Taku Matsushita, Y. Nakano, H. Hiroshi, Naoya Ando, Koichi OhnoAbstract:Geosmin and 2-methylisoborneol (2-MIB) are naturally occurring compounds responsible for musty-earthy-odors in surface water supplies. They are a severe problem confronting utilities worldwide. Adsorption by Powdered Activated Carbon (PAC) is a widely used process to control this problem, but it has low efficiency, which engenders large budget spending for utilities services. Super-Powdered Activated Carbon (S-PAC) is Activated Carbon with much finer particles than those of PAC. Experiments on geosmin and 2-MIB adsorptions on S-PAC and PAC were conducted. Geosmin and 2-MIB adsorption capacities on S-PAC were not smaller than those on PAC although natural organic matter, which adversely impacted the adsorption capacity of geosmin and 2-MIB, was more adsorbed on S-PAC than on PAC, meaning that the adsorption competition is less severe for S-PAC than for PAC.
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Comparison of natural organic matter adsorption capacities of super-Powdered Activated Carbon and Powdered Activated Carbon.
Water Research, 2010Co-Authors: Naoya Ando, Taku Matsushita, Yoshihiko Matsui, Y. Nakano, Ryuji Kurotobi, Koichi OhnoAbstract:We examined the natural organic matter (NOM) adsorption characteristics of super-Powdered Activated Carbon (S-PAC) produced by pulverizing commercially available, normal PAC to a submicron particle size range. The adsorption capacities of S-PAC for NOM and polystyrene sulfonates (PSS) with molecular weights (MWs) of 1.1, 1.8, and 4.6 kDa, which we used as model compounds, were considerably higher than those of PAC. The adsorption capacity increases were observed for all five types of Carbon tested (two wood-based, two coconut-based, and one coal-based Carbon). The adsorption capacities of S-PAC and PAC for polyethylene glycols (PEGs) with MWs of 0.3 and 1.0 were the same. The adsorption capacities of S-PAC for PEGs with MWs of 3.0 and 8.0 kDa were slightly higher than the adsorption capacities of PAC, but the difference in adsorption capacity was not as large as that observed for NOM and the PSSs, even though the MW ranges of the adsorbates were similar. We concluded that the adsorption capacity differences between S-PAC and PAC observed for NOM and PSSs were due to the difference in particle size between the two Carbons, rather than to differences in internal pore size or structure, to differences in activation, or to non-attainment of equilibrium that resulted from the change in particle size. The difference in adsorption capacity between S-PAC and PAC was larger for NOM with a high specific UV absorbance (SUVA) value than for low-SUVA NOM. The larger adsorption capacities of S-PAC compared with PAC were explained by the larger specific external surface area per unit mass. We hypothesize that a larger fraction of the internal pore volume is accessible with Carbon of smaller particle size because the NOM and PSS molecules preferentially adsorb near the outer surface of the particle and therefore do not completely penetrate the adsorbent particle.
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branched pore kinetic model analysis of geosmin adsorption on super Powdered Activated Carbon
Water Research, 2009Co-Authors: Yoshihiko Matsui, Taku Matsushita, Naoya Ando, Hiroshi Sasaki, Koichi OhnoAbstract:Super-Powdered Activated Carbon (S-PAC) is Activated Carbon of much finer particle size than Powdered Activated Carbon (PAC). Geosmin is a naturally occurring taste and odor compound that impairs aesthetic quality in drinking water. Experiments on geosmin adsorption on S-PAC and PAC were conducted, and the results using adsorption kinetic models were analyzed. PAC pulverization, which produced the S-PAC, did not change geosmin adsorption capacity, and geosmin adsorption capacities did not differ between S-PAC and PAC. Geosmin adsorption kinetics, however, were much higher on S-PAC than on PAC. A solution to the branched pore kinetic model (BPKM) was developed, and experimental adsorption kinetic data were analyzed by BPKM and by a homogeneous surface diffusion model (HSDM). The HSDM describing the adsorption behavior of geosmin required different surface diffusivity values for S-PAC and PAC, which indicated a decrease in surface diffusivity apparently associated with Activated Carbon particle size. The BPKM, consisting of macropore diffusion followed by mass transfer from macropore to micropore, successfully described the batch adsorption kinetics on S-PAC and PAC with the same set of model parameter values, including surface diffusivity. The BPKM simulation clearly showed geosmin removal was improved as Activated Carbon particle size decreased. The simulation also implied that the rate-determining step in overall mass transfer shifted from intraparticle radial diffusion in macropores to local mass transfer from macropore to micropore. Sensitivity analysis showed that adsorptive removal of geosmin improved with decrease in Activated Carbon particle size down to 1 μm, but further particle size reduction produced little improvement.
Yoshihiko Matsui - One of the best experts on this subject based on the ideXlab platform.
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Superiority of wet-milled over dry-milled superfine Powdered Activated Carbon for adsorptive 2-methylisoborneol removal.
Water Research, 2016Co-Authors: Yoshihiko Matsui, Taku Matsushita, Nobutaka ShirasakiAbstract:Superfine Powdered Activated Carbon (SPAC), which is produced from conventionally sized Powdered Activated Carbon (PAC) by wet milling in a bead mill, has attracted attention for its high adsorptive removal ability in both research and practice. In this study, the performance of dry-milled SPAC was investigated. 2-Methylisoborneol (MIB), an earthy-musty compound commonly targeted by water treatment systems, was used as the target adsorbate. Dry-milled SPAC exhibited lower adsorptive removal of MIB than wet-milled SPAC, even when both SPACs were produced from the same PAC and were composed of particles of the same size. One reason for the lower removal of MIB by the dry-milled SPAC was a higher degree of aggregation in the dry-milled SPAC after production; as a result the apparent particle size of dry-milled SPAC was larger than that of wet-milled SPAC. The dry-milled SPAC was also more negatively charged than the wet-milled SPAC, and, owing to its higher repulsion, it was more amenable to dispersion by ultrasonication. However, even after the dry-milled SPAC was ultrasonicated so that its apparent particle size was similar to or less than that of the wet-milled SPAC, the dry-milled SPAC was still inferior in adsorptive removal to the wet-milled SPAC. Therefore, another reason for the lower adsorptive removal of dry-milled SPAC was its lower equilibrium adsorption capacity due to the oxidation during the milling. The adsorption kinetics by SPACs with different degrees of particle aggregation were successfully simulated by a pore diffusion model and a fractal aggregation model.
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adsorptive virus removal with super Powdered Activated Carbon
Separation and Purification Technology, 2013Co-Authors: Taku Matsushita, Hideaki Suzuki, Nobutaka Shirasaki, Yoshihiko Matsui, Koichi OhnoAbstract:Abstract We investigated the removal of bacteriophages by adsorption on commercially available Powdered Activated Carbon (N-PAC, median diameter >10 μm) and super-Powdered Activated Carbon (S-PAC, median diameter 0.7–2.8 μm). N-PACs failed to remove the virus in Milli-Q water buffered with 100 μM Ca 2+ , but some S-PACs successfully removed it under the same condition. Three factors contributed substantially to virus removal: a smaller electrophoretic repulsive force between the virus and the PAC particles, a large proportion of pores 20–50 nm in diameter, and a greater hydrophobicity of the virus surface.
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modeling high adsorption capacity and kinetics of organic macromolecules on super Powdered Activated Carbon
Water Research, 2011Co-Authors: Yoshihiko Matsui, Taku Matsushita, Naoya Ando, Tomoaki Yoshida, Ryuji Kurotobi, Koichi OhnoAbstract:The capacity to adsorb natural organic matter (NOM) and polystyrene sulfonates (PSSs) on small particle-size Activated Carbon (super-Powdered Activated Carbon, SPAC) is higher than that on larger particle-size Activated Carbon (Powdered-Activated Carbon, PAC). Increased adsorption capacity is likely attributable to the larger external surface area because the NOM and PSS molecules do not completely penetrate the adsorbent particle; they preferentially adsorb near the outer surface of the particle. In this study, we propose a new isotherm equation, the Shell Adsorption Model (SAM), to explain the higher adsorption capacity on smaller adsorbent particles and to describe quantitatively adsorption isotherms of Activated Carbons of different particle sizes: PAC and SPAC. The SAM was verified with the experimental data of PSS adsorption kinetics as well as equilibrium. SAM successfully characterized PSS adsorption isotherm data for SPACs and PAC simultaneously with the same model parameters. When SAM was incorporated into an adsorption kinetic model, kinetic decay curves for PSSs adsorbing onto Activated Carbons of different particle sizes could be simultaneously described with a single kinetics parameter value. On the other hand, when SAM was not incorporated into such an adsorption kinetic model and instead isotherms were described by the Freundlich model, the kinetic decay curves were not well described. The success of the SAM further supports the adsorption mechanism of PSSs preferentially adsorbing near the outer surface of Activated Carbon particles.
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Geosmin and 2-methylisoborneol adsorption on super-Powdered Activated Carbon in the presence of natural organic matter.
Water Science and Technology, 2010Co-Authors: Yoshihiko Matsui, Taku Matsushita, Y. Nakano, H. Hiroshi, Naoya Ando, Koichi OhnoAbstract:Geosmin and 2-methylisoborneol (2-MIB) are naturally occurring compounds responsible for musty-earthy-odors in surface water supplies. They are a severe problem confronting utilities worldwide. Adsorption by Powdered Activated Carbon (PAC) is a widely used process to control this problem, but it has low efficiency, which engenders large budget spending for utilities services. Super-Powdered Activated Carbon (S-PAC) is Activated Carbon with much finer particles than those of PAC. Experiments on geosmin and 2-MIB adsorptions on S-PAC and PAC were conducted. Geosmin and 2-MIB adsorption capacities on S-PAC were not smaller than those on PAC although natural organic matter, which adversely impacted the adsorption capacity of geosmin and 2-MIB, was more adsorbed on S-PAC than on PAC, meaning that the adsorption competition is less severe for S-PAC than for PAC.
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Comparison of natural organic matter adsorption capacities of super-Powdered Activated Carbon and Powdered Activated Carbon.
Water Research, 2010Co-Authors: Naoya Ando, Taku Matsushita, Yoshihiko Matsui, Y. Nakano, Ryuji Kurotobi, Koichi OhnoAbstract:We examined the natural organic matter (NOM) adsorption characteristics of super-Powdered Activated Carbon (S-PAC) produced by pulverizing commercially available, normal PAC to a submicron particle size range. The adsorption capacities of S-PAC for NOM and polystyrene sulfonates (PSS) with molecular weights (MWs) of 1.1, 1.8, and 4.6 kDa, which we used as model compounds, were considerably higher than those of PAC. The adsorption capacity increases were observed for all five types of Carbon tested (two wood-based, two coconut-based, and one coal-based Carbon). The adsorption capacities of S-PAC and PAC for polyethylene glycols (PEGs) with MWs of 0.3 and 1.0 were the same. The adsorption capacities of S-PAC for PEGs with MWs of 3.0 and 8.0 kDa were slightly higher than the adsorption capacities of PAC, but the difference in adsorption capacity was not as large as that observed for NOM and the PSSs, even though the MW ranges of the adsorbates were similar. We concluded that the adsorption capacity differences between S-PAC and PAC observed for NOM and PSSs were due to the difference in particle size between the two Carbons, rather than to differences in internal pore size or structure, to differences in activation, or to non-attainment of equilibrium that resulted from the change in particle size. The difference in adsorption capacity between S-PAC and PAC was larger for NOM with a high specific UV absorbance (SUVA) value than for low-SUVA NOM. The larger adsorption capacities of S-PAC compared with PAC were explained by the larger specific external surface area per unit mass. We hypothesize that a larger fraction of the internal pore volume is accessible with Carbon of smaller particle size because the NOM and PSS molecules preferentially adsorb near the outer surface of the particle and therefore do not completely penetrate the adsorbent particle.
Taku Matsushita - One of the best experts on this subject based on the ideXlab platform.
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Superiority of wet-milled over dry-milled superfine Powdered Activated Carbon for adsorptive 2-methylisoborneol removal.
Water Research, 2016Co-Authors: Yoshihiko Matsui, Taku Matsushita, Nobutaka ShirasakiAbstract:Superfine Powdered Activated Carbon (SPAC), which is produced from conventionally sized Powdered Activated Carbon (PAC) by wet milling in a bead mill, has attracted attention for its high adsorptive removal ability in both research and practice. In this study, the performance of dry-milled SPAC was investigated. 2-Methylisoborneol (MIB), an earthy-musty compound commonly targeted by water treatment systems, was used as the target adsorbate. Dry-milled SPAC exhibited lower adsorptive removal of MIB than wet-milled SPAC, even when both SPACs were produced from the same PAC and were composed of particles of the same size. One reason for the lower removal of MIB by the dry-milled SPAC was a higher degree of aggregation in the dry-milled SPAC after production; as a result the apparent particle size of dry-milled SPAC was larger than that of wet-milled SPAC. The dry-milled SPAC was also more negatively charged than the wet-milled SPAC, and, owing to its higher repulsion, it was more amenable to dispersion by ultrasonication. However, even after the dry-milled SPAC was ultrasonicated so that its apparent particle size was similar to or less than that of the wet-milled SPAC, the dry-milled SPAC was still inferior in adsorptive removal to the wet-milled SPAC. Therefore, another reason for the lower adsorptive removal of dry-milled SPAC was its lower equilibrium adsorption capacity due to the oxidation during the milling. The adsorption kinetics by SPACs with different degrees of particle aggregation were successfully simulated by a pore diffusion model and a fractal aggregation model.
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adsorptive virus removal with super Powdered Activated Carbon
Separation and Purification Technology, 2013Co-Authors: Taku Matsushita, Hideaki Suzuki, Nobutaka Shirasaki, Yoshihiko Matsui, Koichi OhnoAbstract:Abstract We investigated the removal of bacteriophages by adsorption on commercially available Powdered Activated Carbon (N-PAC, median diameter >10 μm) and super-Powdered Activated Carbon (S-PAC, median diameter 0.7–2.8 μm). N-PACs failed to remove the virus in Milli-Q water buffered with 100 μM Ca 2+ , but some S-PACs successfully removed it under the same condition. Three factors contributed substantially to virus removal: a smaller electrophoretic repulsive force between the virus and the PAC particles, a large proportion of pores 20–50 nm in diameter, and a greater hydrophobicity of the virus surface.
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modeling high adsorption capacity and kinetics of organic macromolecules on super Powdered Activated Carbon
Water Research, 2011Co-Authors: Yoshihiko Matsui, Taku Matsushita, Naoya Ando, Tomoaki Yoshida, Ryuji Kurotobi, Koichi OhnoAbstract:The capacity to adsorb natural organic matter (NOM) and polystyrene sulfonates (PSSs) on small particle-size Activated Carbon (super-Powdered Activated Carbon, SPAC) is higher than that on larger particle-size Activated Carbon (Powdered-Activated Carbon, PAC). Increased adsorption capacity is likely attributable to the larger external surface area because the NOM and PSS molecules do not completely penetrate the adsorbent particle; they preferentially adsorb near the outer surface of the particle. In this study, we propose a new isotherm equation, the Shell Adsorption Model (SAM), to explain the higher adsorption capacity on smaller adsorbent particles and to describe quantitatively adsorption isotherms of Activated Carbons of different particle sizes: PAC and SPAC. The SAM was verified with the experimental data of PSS adsorption kinetics as well as equilibrium. SAM successfully characterized PSS adsorption isotherm data for SPACs and PAC simultaneously with the same model parameters. When SAM was incorporated into an adsorption kinetic model, kinetic decay curves for PSSs adsorbing onto Activated Carbons of different particle sizes could be simultaneously described with a single kinetics parameter value. On the other hand, when SAM was not incorporated into such an adsorption kinetic model and instead isotherms were described by the Freundlich model, the kinetic decay curves were not well described. The success of the SAM further supports the adsorption mechanism of PSSs preferentially adsorbing near the outer surface of Activated Carbon particles.
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Geosmin and 2-methylisoborneol adsorption on super-Powdered Activated Carbon in the presence of natural organic matter.
Water Science and Technology, 2010Co-Authors: Yoshihiko Matsui, Taku Matsushita, Y. Nakano, H. Hiroshi, Naoya Ando, Koichi OhnoAbstract:Geosmin and 2-methylisoborneol (2-MIB) are naturally occurring compounds responsible for musty-earthy-odors in surface water supplies. They are a severe problem confronting utilities worldwide. Adsorption by Powdered Activated Carbon (PAC) is a widely used process to control this problem, but it has low efficiency, which engenders large budget spending for utilities services. Super-Powdered Activated Carbon (S-PAC) is Activated Carbon with much finer particles than those of PAC. Experiments on geosmin and 2-MIB adsorptions on S-PAC and PAC were conducted. Geosmin and 2-MIB adsorption capacities on S-PAC were not smaller than those on PAC although natural organic matter, which adversely impacted the adsorption capacity of geosmin and 2-MIB, was more adsorbed on S-PAC than on PAC, meaning that the adsorption competition is less severe for S-PAC than for PAC.
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Comparison of natural organic matter adsorption capacities of super-Powdered Activated Carbon and Powdered Activated Carbon.
Water Research, 2010Co-Authors: Naoya Ando, Taku Matsushita, Yoshihiko Matsui, Y. Nakano, Ryuji Kurotobi, Koichi OhnoAbstract:We examined the natural organic matter (NOM) adsorption characteristics of super-Powdered Activated Carbon (S-PAC) produced by pulverizing commercially available, normal PAC to a submicron particle size range. The adsorption capacities of S-PAC for NOM and polystyrene sulfonates (PSS) with molecular weights (MWs) of 1.1, 1.8, and 4.6 kDa, which we used as model compounds, were considerably higher than those of PAC. The adsorption capacity increases were observed for all five types of Carbon tested (two wood-based, two coconut-based, and one coal-based Carbon). The adsorption capacities of S-PAC and PAC for polyethylene glycols (PEGs) with MWs of 0.3 and 1.0 were the same. The adsorption capacities of S-PAC for PEGs with MWs of 3.0 and 8.0 kDa were slightly higher than the adsorption capacities of PAC, but the difference in adsorption capacity was not as large as that observed for NOM and the PSSs, even though the MW ranges of the adsorbates were similar. We concluded that the adsorption capacity differences between S-PAC and PAC observed for NOM and PSSs were due to the difference in particle size between the two Carbons, rather than to differences in internal pore size or structure, to differences in activation, or to non-attainment of equilibrium that resulted from the change in particle size. The difference in adsorption capacity between S-PAC and PAC was larger for NOM with a high specific UV absorbance (SUVA) value than for low-SUVA NOM. The larger adsorption capacities of S-PAC compared with PAC were explained by the larger specific external surface area per unit mass. We hypothesize that a larger fraction of the internal pore volume is accessible with Carbon of smaller particle size because the NOM and PSS molecules preferentially adsorb near the outer surface of the particle and therefore do not completely penetrate the adsorbent particle.
Shinichiro Ohgaki - One of the best experts on this subject based on the ideXlab platform.
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Powdered Activated Carbon and biofiltration improve MF performance: Part II
Membrane Technology, 2007Co-Authors: Mohiuddin Md. Taimur Khan, Warren L. Jones, Anne K. Camper, Satoshi Takizawa, Hiroyuki Katayama, Futoshi Kurisu, Shinichiro OhgakiAbstract:This article shows how the use of high-dose Powdered Activated Carbon and biofiltration are able to improve the performance of membrane-based microfiltration systems. The first part of this feature, which was published in the May 2007 issue of Membrane Technology , provides an overview of the study, materials and methods, and experimental design and operational conditions of the reactors. The second instalment, which appears here, discusses the results of this study.
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application of microfiltration systems coupled with Powdered Activated Carbon to river water treatment
Desalination, 2007Co-Authors: Satoshi Takizawa, Shinichiro OhgakiAbstract:Abstract A bench scale submerged microfiltration system coupled with high concentration of PAC (Powdered Activated Carbon) was applied in order to purify a river water containing secondary effluent. The system was operated with four different modes: Run-1, -2, -3 and -4. The PAC concentration was set at 0, 4 and 40 g/L with same filtration rate of 1.0 m/d (42 L/m 2 /h) which correspond to Run-1, -2 and -3. In Run-4, the filtration rate was set at 0.5 m/d (21 L/m 2 /h) with PAC concentration of 40 g/L. The effluent turbidity showed below 0.1 NTU for all runs, and the removal rates more than 90% were observed. As for TOC removal, almost no removal of TOC was observed in Run-1 while the higher removal rates were obtained with the higher dosage of Powdered Activated Carbon. Run-3 and 4 with PAC dose of 40 g/L showed the removal of 85% regardless of the filtration rates. Removal of UV254 was similar to that of TOC: removal of 13% at Run-1 and 90% at Run-3 and -4. As for the filtration efficiency, an average filtration time for TMP to reach 60 kPa was checked for each runs. The filtration time of around 5 days was observed in Run-1 and Run-2, 2 days in Run-3 and 60 days in Run-4. According to the results, the effluent water quality got better with higher dose of PAC and the filtration efficiency was enhanced with higher dose of PAC and lower filtration time.
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sorption characteristics of biological Powdered Activated Carbon in bpac mf biological Powdered Activated Carbon microfiltration system for refractory organic removal
Water Science and Technology, 1997Co-Authors: Shinichiro Ohgaki, Y SuzukiAbstract:The sorption characteristic of biological Powdered Activated Carbon (BPAC) were investigated in a hybrid membrane process which was accomplished by introducing Powdered Activated Carbon (PAC) into a crossflow microfiltration system and seeding microorganisms. This combined process was designated BPAC-MF and could be an alternative system for reclamation of secondary sewage effluent. Experiments were carried out to identify the ability of BPAC to remove various dissolved refractory organic matter in secondary sewage effluents such as peptone, beef extract, lauryl sulfate, humic acid, tannin, lignin and gum arabic. Adsorption test by fresh Powdered Activated Carbon (PAC) showed significantly different adsorption characteristics for each organic substance. These adsorption characteristics were identified by the analysis of gel permeable chromatography (GPC). The sorptive capacity of BPAC was almost four times higher than that of fresh PAC. This phenomenon could be explained from the sorption capacity of PAC and BPAC for each substance. For the hardly adsorbable refractory organics, humic acid and gum arabic, the sorption capacity of bPAC was 12.1 and 8.7 mg/g respectively. These values are significantly high compared with 3.6 and 0.2 mg/g obtained by PAC. It was estimated that the enhanced sorption capacity of BPAC was due to the stimulation of Activated Carbon adsorption by biological effect.
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biological Powdered Activated Carbon bpac microfiltration for wastewater reclamation and reuse
Desalination, 1996Co-Authors: Y Suzuki, Shinichiro OhgakiAbstract:Abstract The experiment was conducted to evaluate a biological Powdered Activated Carbon (BPAC) microfiltration (MF) system as an alternative for wastewater reclamation and reuse. A synthetic secondary sewage effluent contains refractory organic compounds such as humin, tannin, lignin, protein and high molecular carbohydrates as well as coliphage Qs as a model virus. The system performance was investigated at the Activated Carbon concentration of 20 g/1, water temperature 25°C and transmembrane pressure of 55 kPa. It was noted that organic removal occurred mainly at the membrane module. This was caused by the accumulation of the Powdered Activated Carbon in the membrane module. The average organic removal efficiency was 83%, resulting in an effluent TOC concentration of 1–2 mg/1. The performance of the process did not deteriorate at water temperature of 15°C, showing an organic removal efficiency of 89.6%. It was estimated that the higher removal efficiency at lower water temperature was mainly due to the less self-degradation of microorganisms because the permeate flux of the membrane was maintained at the same level by increasing the transmembrane pressure up to 80 kPa. The removal of virus by the BPAC-MF system was significant. From the mass balance at steady state, 99.9997% of fed coliphage Qs was removed from the system. Especially coliphage Qs showed a strong adsorbability on Powdered Activated Carbon (PAC). For 1 h contact with PAC, the removal of Qs was 99.999% even at PAC concentrations of 0.55 g/l. It was obvious that the virus removed was inActivated in the system.
Wilson Beitasandi - One of the best experts on this subject based on the ideXlab platform.
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removal of n nitrosodimethylamine precursors with Powdered Activated Carbon adsorption
Water Research, 2016Co-Authors: Wilson Beitasandi, Mahmut S Ersan, Habibullah Uzun, Tanju KaranfilAbstract:Abstract The main objective of this study was to examine the roles of Powdered Activated Carbon (PAC) characteristics (i.e., surface chemistry, pore size distribution, and surface area) in the removal of N-nitrosodimethylamine (NDMA) formation potential (FP) in surface and wastewater-impacted waters. Also, the effects of natural attenuation of NDMA precursors in surface waters, NDMA FP concentration, and Carbon dose on the removal of NDMA FP by PAC were evaluated. Finally, the removal of NDMA FP by PAC at two full-scale DWTPs was monitored. Wastewater-impacted and surface water samples were collected to conduct adsorption experiments using different PACs and Activated Carbon fibers (ACFs) with a wide range of physicochemical characteristics. The removal efficiency of NDMA FP by PAC was significantly higher in wastewater-impacted than surface waters. Adsorbable NDMA precursors showed a size distribution in the waters tested; the adsorbable fraction included precursors accessing the pore size regions of 10–20 A and
